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            <h2 class="title"><a id="am_misc"></a>Chapter 4.  Access Method Wrapup </h2>
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          <b>Table of Contents</b>
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        <dl>
          <dt>
            <span class="sect1">
              <a href="am_misc.html#am_misc_align">Data alignment</a>
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          <dt>
            <span class="sect1">
              <a href="am_misc_bulk.html">Retrieving and updating records in bulk</a>
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              <dt>
                <span class="sect2">
                  <a href="am_misc_bulk.html#am_misc_bulk_get">Bulk retrieval</a>
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              <dt>
                <span class="sect2">
                  <a href="am_misc_bulk.html#am_misc_bulk_put">Bulk updates</a>
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              <dt>
                <span class="sect2">
                  <a href="am_misc_bulk.html#am_misc_bulk_del">Bulk deletes</a>
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              <a href="am_misc_partial.html">Partial record storage and
        retrieval</a>
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            <span class="sect1">
              <a href="am_misc_struct.html">Storing C/C++
        structures/objects</a>
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          <dt>
            <span class="sect1">
              <a href="am_misc_perm.html">Retrieved key/data permanence for C/C++</a>
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            <span class="sect1">
              <a href="am_misc_error.html">Error support</a>
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            <span class="sect1">
              <a href="am_misc_stability.html">Cursor stability</a>
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              <a href="am_misc_dbsizes.html">Database limits</a>
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            <span class="sect1">
              <a href="am_misc_diskspace.html">Disk space
        requirements</a>
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            <span class="sect1">
              <a href="blobs.html">External File support</a>
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              <dt>
                <span class="sect2">
                  <a href="blobs.html#blob_threshold">The external file threshold</a>
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              <dt>
                <span class="sect2">
                  <a href="blobs.html#blob_create">Creating external files</a>
                </span>
              </dt>
              <dt>
                <span class="sect2">
                  <a href="blobs.html#blob_access">External file access</a>
                </span>
              </dt>
              <dt>
                <span class="sect2">
                  <a href="blobs.html#blob_storage">External file storage</a>
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                <span class="sect2">
                  <a href="blobs.html#blob_replication">External Files and Replication</a>
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          <dt>
            <span class="sect1">
              <a href="am_misc_db_sql.html">Specifying a Berkeley DB schema
        using SQL DDL</a>
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          </dt>
          <dt>
            <span class="sect1">
              <a href="am_misc_tune.html">Access method tuning</a>
            </span>
          </dt>
          <dt>
            <span class="sect1">
              <a href="am_misc_faq.html">Access method FAQ</a>
            </span>
          </dt>
        </dl>
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      <div class="sect1" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h2 class="title" style="clear: both"><a id="am_misc_align"></a>Data alignment</h2>
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        <p>
        The Berkeley DB access methods provide no guarantees about
        byte alignment for returned key/data pairs, or callback
        functions which take <a href="../api_reference/C/dbt.html" class="olink">DBT</a> references as arguments, and
        applications are responsible for arranging any necessary
        alignment. The <a href="../api_reference/C/dbt.html#dbt_DB_DBT_MALLOC" class="olink">DB_DBT_MALLOC</a>, <a href="../api_reference/C/dbt.html#dbt_DB_DBT_REALLOC" class="olink">DB_DBT_REALLOC</a>, and
        <a href="../api_reference/C/dbt.html#dbt_DB_DBT_USERMEM" class="olink">DB_DBT_USERMEM</a> flags may be used to store returned items in
        memory of arbitrary alignment.
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